An axial flow fan improves air capacity and static pressure characteristics, and can ease stress at a leading edge portion of a blade base, even when a shape for noise reduction is adopted. An axial flow fan includes a boss portion and rotor blades. A rotor blade is segmented into a first area extending from the boss portion toward the outer peripheral side, and a second area connected to the first area and extending from the first area to the outermost periphery of the rotor blade. The distribution of a forward sweep angle varies quadratically in the first area, and the maximum forward sweep angle in the first area is not larger than the forward sweep angle in the second area. The distribution of chord-pitch ratio varies in a curved manner from the base as the minimum value in the first area, and is linear in the second area.